[boba7523]

Hi all, I'm fairly new in the world of suspensions and would like to know what the benefits are of say getting an aftermarket control arm and tie rods such as SPL? With a camber plate, I can essentially adjust the camber to be very aggressive already and toe adjustment doesn't seem to be an issue with stock tie rods.

I've heard about lighter spring weight which would potentially make the tires make better contact with the ground, but are there other benefits? I take my car out to track once in a while.

Thanks!

[Westersund]

The stock control arms are made out of aluminium and very light, the only thing you really need to change up front is the front rubber bushing on the thrust arm and the camber plates. You will retain sealed ball joints that doesn't need attention everytime you've driven the car in rain.
In my opinion SPL arms and similar are only for comitted track/race cars. But if you want to run SPL arms on a daily driven car you should consider the rod ends as service items with significantly shorter life span than stock (sealed) ball joints.

[HP Autosport]

Originally Posted by boba7523

Hi all, I'm fairly new in the world of suspensions and would like to know what the benefits are of say getting an aftermarket control arm and tie rods such as SPL? With a camber plate, I can essentially adjust the camber to be very aggressive already and toe adjustment doesn't seem to be an issue with stock tie rods.

I've heard about lighter spring weight which would potentially make the tires make better contact with the ground, but are there other benefits? I take my car out to track once in a while.

Thanks!

Typically they give much less deflection to keep the the camber and toe more under control. At some extreme settings toe links will take away the bind and allow more adjustment that wasn't there before.

The performance of your dampers is directly related to the quality of your springs. Higher quality and lighter springs will certainly make a difference. Your dampers don't have to work as hard to control them. Swift has one of the lightest springs with the thinnest coils(more stroke) on the market today.

Feel free to PM us if you have more specific questions regarding SPL or Swift.

[look585]

For me this is a must.

Solid toe links. The bar links installed are only if I go coil over later, really not necessary.

[///MPhatic]

Originally Posted by Westersund

The only thing you really need to change up front is the front rubber bushing on the thrust arm...

What's the reason for this?

[Westersund]

Originally Posted by ///MPhatic

What's the reason for this?

It makes the car more stable. You could change out everything if you want to go all out. But I think the thrust arm bushings and camber plates cover most peoples needs.

[///MPhatic]

Originally Posted by Westersund

It makes the car more stable. You could change out everything if you want to go all out. But I think the thrust arm bushings and camber plates cover most peoples needs.

Thanks for the info. I don't track my car, but I'm always after the low-hanging fruit with regards to better performance for a bit more money. I know that leaves camber plates out, but I'm not sure about this bushing.

[Westersund]

If you don't track the car I would say you don't need to change out the bushings in the thrust arms. Even if the M2 is stable from the factory the bushings helps with high speed braking/cornering.

[D.Yooras]

Originally Posted by Westersund

It makes the car more stable. You could change out everything if you want to go all out. But I think the thrust arm bushings and camber plates cover most peoples needs.

I tend to agree with this with a caveat, going spherical makes the front end of the car noticeably more harsh and certainly louder. Unless the car was a dedicated track car, or weekend warrior, I wouldn't make the compromise for spherical front compliance bushings. That said, a car that has them has razor sharp front axle feedback and control which is very beneficial on the track or during aggressive street driving.

The one thing that I'll add is big front sway bar on these cars is probably the best bang for the buck mod you can do. I'd say almost more than camber plates, plus it's a fairly easier DIY, and has nearly no change in NVH on regular roads.

Otherwise, most aftermarket arms are not needed and can be detrimental to handling. One of the aspects of suspension people seem to miss is that adjustable length control arms do NOT have the same effect as eccentric adjuster (adjustable mounting position).

Changing the mounting position of an arm (ie eccentric adjuster) simply changes the angular relationship between two suspension components. This does keeps the suspension virtually unchanged, it just shifts the start point of the geometry curve rather than shifting the curve itself. Changing the length of a control arm affects the geometric starting point AND the curve throughout it's range of travel, in addition to that arm's relationship with other control arms.

This isn't a bad thing IF you know what changes are being made to the geometry of the car both at ride height and throughout the range of travel. That's why most people should stay away from aftermarket control arms because unless you know exactly what the arm is doing, and have an alignment shop you can take the car to do perform the adjustments the correct way, you could end up making your car handle worse than it did before. Even then, the only adjustable arms I'd recommend are front control arms since the geometry up front is far less complex than the rear.

In general, modern BMW's are an easy formula (suspension only).

Stage 1 (street use): Install front camber plates, bigger front sway bar, and adjustable coilover suspension if desired (but really not needed for most people).
Stage 2 (aggressive street and/or some track): Adjustable end links and proper corner balancing, coil overs are practically a must have
Stage 3 (dedicated track car or aggressive dual duty): Adjustable front lower control arms (both track arm and tension arm) to allow for adjust-ability of camber, caster, and track width.

Anything from that point forward is usually dedicated race car stuff.